This invention relates to automatic water heaters and the dispensing of heated water for any purpose, for example, for making hot beverages such as tea, instant coffee and cocoa; and more particularly the invention contemplates the pouring of hot water over ground coffee in a manner suitable to the methods of percolator, filter or drip coffee making.
To heat the water and accomplish the above by the methods of the prior art, the water is made to flow through tubing, pipes or containers which are heated by electric heaters attached to the outside or mounted on the inside of the pipes or containers. The piping arrangement through which the water has to flow to be heated is practically inaccessible for cleaning.
In the process of heating the water with devices or apparatus of this character, many of the minerals contained in the water adhere to the hot surfaces and form a tight scale. As a result of the repeated use of the apparatus this tight scale of mineral deposits builds up in thickness, which reduces the proper heat transfer and will in time prevent the heating function, unless the scale is removed.
To remove the scale, prevent the excessive scale build up and clean the heating surfaces, a suitable washing solution such as vinegar and water in equal parts must be run through the heating cycle of the unit, preferably more than once, with interruption to make allowance for soaking time. This cleaning method must be followed by a thorough rinsing and must be continued on an approximate monthly schedule for the life of the heating unit.